| # | Company | Employees |
|---|---|---|
| 1 |
SNC-Lavalinatkinsrealis.com
Global engineering services and nuclear organization connecting people, data, and technology to transform infrastructure and energy systems worldwide. |
11,913 |
| 2 | 6,113 | |
| 3 | 4,739 | |
| 4 |
Raymond Chabot Grant Thorntonrcgt.com
A leading accounting firm with over 2,300 professionals offering assurance, taxation, consulting, and business recovery services in Quebec and globally |
2,426 |
| 5 |
Alithyaalithya.com
A global digital technology services company providing practical IT solutions tailored to complex business challenges, with a focus on strategy and digital transformation |
2,418 |
| 6 |
BBA Consultantsbbaconsultants.com
Innovative engineering solutions provider assisting industries in transitioning to a sustainable future through sharp business acumen and vast technological curiosity |
2,381 |
| 7 |
Syntaxsyntax.com
A leading Managed Cloud Provider offering ERP solutions, consulting services, security, and support for businesses worldwide in various industries |
2,193 |
| 8 |
OSF Digitalosf.digital
Top global company offering data-driven AI-powered Salesforce multi-cloud solutions, enterprise CRM, CMS, OMS, connected commerce, online shop management, and cloud application development for businesses. |
1,867 |
| 9 |
Mallettemallette.ca
Provides extensive accounting, advisory, and client-focused services through numerous Quebec offices, supporting local and international business needs. |
1,303 |
| 10 | 1,278 | |
| 11 | 1,269 | |
| 12 |
COFOMOcofomo.com
Canadian IT and business consulting leader specializing in digital transformation with a team of 3,000 professionals offering innovative solutions nationwide |
1,201 |
| 13 |
AVENIR GLOBALavenir.global
A global holding and management group with specialized communication agencies in Canada, the US, Europe, and the Middle East |
1,020 |
| 14 |
Richterrichter.ca
Business | Family Office providing strategic advice on business and family matters, guiding successful entrepreneurs to shape their legacy across generations |
922 |
| 15 |
Norda Stelonorda.com
Canadian engineering firm specializing in integrated projects in transportation and various industries, committed to quality, innovation, value creation, and sustainability |
805 |
| 16 |
Stantec au Québecstantec.com
Global leader in engineering and sustainable development, with expertise in various sectors, providing services from concept to completion with innovation and client needs in mind |
801 |
| 17 |
LGS, an IBM Companylgs.com
Global company affiliated with IBM offering IT solutions, services, and resources including cloud computing, AI, and application services, with a focus on innovation and excellence in Quebec |
752 |
| 18 |
SNC-Lavalin Rail & Transit (formerly Interfleet)snclavalin.com
Global engineering and construction group providing industry-leading services in infrastructure, oil and gas, mining, power, and rail and transit systems |
659 |
| 19 |
Artelia Canadaarteliagroup.ca
Multidisciplinary engineering firm providing innovative solutions in mobility, energy, environment, water, industry, and telecom across Canada with global expertise. |
642 |
| 20 | 614 | |
| 21 |
Optimum Financial Groupoptimumfinancier.com
Financial group providing services in actuarial consulting, asset management, insurance, IT, and real estate Operating globally with over 600 employees and significant assets under management |
559 |
| 22 |
ALTEN Canadaalten.ca
Global consulting firm specializing in Engineering and IT, with over 30 years experience Providing specialized professionals, tailored solutions, and employee-focused support |
318 |
| 23 |
IVADO Labsivadolabs.com
An interdisciplinary team leveraging artificial intelligence to address unique business challenges and drive meaningful outcomes for industries and enterprises |
143 |
| 24 |
Datmosdatmos.com
An award-winning agency specializing in scalable e-commerce solutions for B2B, D2C, and B2C, helping companies think, build, run, and scale their online presence |
104 |
| 25 |
Talan | Planaxistalan.com
A Canadian IT consulting firm specializing in digital transformation projects for major industries, offering tailored solutions in Big Data, AI, IoT, Blockchain, and more |
93 |
| 26 |
Énergèreenergere.com
A leading energy services company specializing in energy efficiency, greenhouse gas reductions, smart cities, and intelligent buildings across Canada and the United States |
78 |
| 27 |
Assystem Technologies Canadaassystemtechnologies.com
A global engineering partner providing quality services and digital solutions to clients in aerospace, automotive, defense, finance, industry, and transportation sectors |
72 |
| 28 | 63 | |
| 29 |
Videns, propulsée par COFOMOvidens.ai
Support organizations by leveraging data and advanced artificial intelligence technologies to implement effective, sustainable, and ethical processes aligned with human values. |
36 |
| 30 |
Menyamenyasolutions.com
Developing AI software systems to automate decision-making processes in various sectors, using machine learning, data science, computer vision, and more |
19 |
| 31 | 18 | |
| 32 |
TransGlobe Logistiquestransglobelogistiques.com
Connecting clients with transport and logistics providers by simplifying supplier selection process, facilitating client development, and establishing strong partnerships for customer satisfaction |
8 |
| 33 |
Groupe CFO Conseilgroupecfoconseil.com
With over 20 years of experience, CFO Conseil offers financial engineering solutions to help entrepreneurs navigate complex growth challenges and secure financing |
5 |
| 34 |
Leap Conseilleapconseil.com
Leap Conseil specializes in artificial intelligence, aiming to democratize AI technologies within small to medium-sized businesses and organizations to boost productivity |
4 |
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How this list is built
Every company on this list has a Tamtam company profile. The industry is the one the company gives on LinkedIn; categories such as SaaS or fintech are classified by Tamtam's AI from the company's website and LinkedIn page; and the headquarters city must match the company's own address. Companies are ranked by the number of employees on LinkedIn, and the list is refreshed every night. Classifications can be wrong, so treat the list as a starting point rather than an official ranking. Last updated Oct 24, 2026.
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